Re: [GIT PULL] s390 updates for 5.15 merge window

[Christian Borntraeger]

On 31.08.21 04:19, Nathan Chancellor wrote:
> Hi Heiko,
>
> On Mon, Aug 30, 2021 at 03:11:50PM +0200, Heiko Carstens wrote:
> > - Enable KCSAN for s390. This comes with a small common code change to fix a
> >    compile warning. Acked by Marco Elver:
> >    https://lore.kernel.org/r/20210729142811.1309391-1-hca@xxxxxxxxxxxxx/
>
> This caught my eye, as we are boot testing KCSAN + KCSAN_KUNIT_TEST in
> our CI [1] for x86_64 so it would be nice to enable this for s390 as
> well. However, it does not seem like the unit tests pass when booting up
> in QEMU, is this expected or am I doing something wrong? The results and
> compiler versions are below (the results are the same), they should both
> have the commits that are mentioned in the KCSAN message.

Do you have a branch somewhere where you have the s390 build rules as well as
the qemu command line? Maybe its a QEMU TCG issue, dont know. CC qemu-s390x
just in case.

FWIW, if you want access to a virtual s390x let me know.

> GCC 12.0.0 @ d904008df267cbcc01bd6edf98fa0789fb6e94da
>
> [  131.813482]     not ok 1 - test_basic
> [  135.321137]     not ok 2 - test_concurrent_races
> [  138.830648]     ok 3 - test_novalue_change
> [  142.342562]     not ok 4 - test_novalue_change_exception
> [  145.851008]     not ok 5 - test_unknown_origin
> [  149.361416]     ok 6 - test_write_write_assume_atomic
> [  152.872013]     not ok 7 - test_write_write_struct
> [  156.382960]     not ok 8 - test_write_write_struct_part
> [  159.890222]     ok 9 - test_read_atomic_write_atomic
> [  163.402919]     not ok 10 - test_read_plain_atomic_write
> [  166.912931]     not ok 11 - test_read_plain_atomic_rmw
> [  170.431915]     not ok 12 - test_zero_size_access
> [  173.940959]     ok 13 - test_data_race
> [  177.452028]     not ok 14 - test_assert_exclusive_writer
> [  180.962840]     not ok 15 - test_assert_exclusive_access
> [  184.474686]     not ok 16 - test_assert_exclusive_access_writer
> [  187.992282]     not ok 17 - test_assert_exclusive_bits_change
> [  191.501869]     ok 18 - test_assert_exclusive_bits_nochange
> [  195.013138]     not ok 19 - test_assert_exclusive_writer_scoped
> [  199.534212]     not ok 20 - test_assert_exclusive_access_scoped
> [  203.053361]     ok 21 - test_jiffies_noreport
> [  206.573803]     ok 22 - test_seqlock_noreport
> [  210.093508]     ok 23 - test_atomic_builtins
> [  210.094014] not ok 1 - kcsan
>
> clang 14.0.0 @ 657bb7262d4a53e903e702d46fdcab57b7085128:
>
> [   10.341427]     not ok 1 - test_basic
> [   13.848960]     not ok 2 - test_concurrent_races
> [   17.359671]     ok 3 - test_novalue_change
> [   20.869202]     not ok 4 - test_novalue_change_exception
> [   24.379067]     not ok 5 - test_unknown_origin
> [   27.889492]     ok 6 - test_write_write_assume_atomic
> [   31.399572]     not ok 7 - test_write_write_struct
> [   34.910833]     not ok 8 - test_write_write_struct_part
> [   38.419473]     ok 9 - test_read_atomic_write_atomic
> [   41.929642]     not ok 10 - test_read_plain_atomic_write
> [   45.439644]     not ok 11 - test_read_plain_atomic_rmw
> [   48.950048]     not ok 12 - test_zero_size_access
> [   52.459026]     ok 13 - test_data_race
> [   55.969806]     not ok 14 - test_assert_exclusive_writer
> [   59.480436]     not ok 15 - test_assert_exclusive_access
> [   62.990164]     not ok 16 - test_assert_exclusive_access_writer
> [   66.499199]     not ok 17 - test_assert_exclusive_bits_change
> [   70.009481]     ok 18 - test_assert_exclusive_bits_nochange
> [   73.522184]     not ok 19 - test_assert_exclusive_writer_scoped
> [   78.030448]     not ok 20 - test_assert_exclusive_access_scoped
> [   81.539059]     ok 21 - test_jiffies_noreport
> [   85.051769]     ok 22 - test_seqlock_noreport
> [   88.572048]     ok 23 - test_atomic_builtins
> [   88.572279] not ok 1 - kcsan
>
> [1]: https://github.com/ClangBuiltLinux/continuous-integration2
>
> Cheers,
> Nathan